A plastisol composition comprising polyvinyl chloride as a main component has been employed as adhesives, sealant or coating material in various fields. As such a type of plastisol composition, for example, there is known a composition which comprises a polyvinyl chloride, a plasticizer and a blocked compound of diisocyanate polymer with a long-chain alkylated phenol as an adhesion-modifier (cf. Japanese Patent First Publication No. 41278/1987). This plastisol composition, however, has been found to have less adhesion properties under low temperature conditions such as 110.degree. to 130.degree. C., though it has an excellent storage stability under conditions of high temperature and high humidity without foaming and discoloration and is capable of forming a gelated compound with an excellent adhesion strength under high temperature conditions.